I'm swooping down a delectable gladed run in fresh, dry, light powder. We're high above the Columbia River and the cute little Victorian railway township of Revelstoke. The town was once a key stop for the great Canadian Pacific Railroad (it is named after Lord Revelstoke, a London financier who saved the CPR from bankruptcy), but with the lumber industry in decline and the importance of the railway falling, the boom time left town long ago, and for years it has struggled to stop its young people drifting away.

Now though, everything is changing. This sleepy town of 8,500 people in a snow-laden valley between the Monashee and the Selkirk ranges, has found itself at the centre of the biggest thing to happen in North American skiing for years.

With what developers claim to be a billion Canadian dollars (£490m) of investment, Revelstoke is being transformed into a vast ski resort that will rival Whistler, and Vail in Colorado, for the title of the best ski area on the continent. As well as conventional skiing on runs which receive between 40ft and 60ft of snow each year, the new 'Revelstoke Mountain Resort' will be a centre for heliskiing and cat skiing (where skiers are ferried up remote peaks in caterpillar-tread vehicles).

The new resort opened three days before Christmas, but development will continue for up to 15 years - the key milestone being the installation for next winter's season of a lift that will allow the resort to claim a vertical drop (from top lift to bottom run) of almost 6,000ft. This will be the biggest in North America, where 'vertical' is seen as a key yardstick of a resort's quality, and on this measure at least, will see Revelstoke snatch supremacy from Whistler.

Until now, the only skiers who were aware of Revelstoke were heliskiers who thought nothing of spending $7,000 dollars on a week's holiday, not including flights. With two major players, Canadian Mountain Holidays and Selkirk Tangiers Heliskiing, Revelstoke had enjoyed a reputation as the heliskiing capital of the world. But in terms of 'ordinary' skiing - the kind enjoyed by local families in search of a traditional day 'on the hill' that would not cost the earth - Revelstoke had little to offer except a tiny resort known as Powder Springs at the base of Mount MacKenzie.

It had just two lifts, one of which - a rather ancient double chair - was known affectionately as the Powder Slug.

What few people realised was that at 8,029ft, Mount MacKenzie was actually a slumbering giant, a skiers' dream with the potential to form a world-beating resort. When I tried it, a few days after the resort opened, the new lifts made its strengths abundantly clear.

There are consistently steep and challenging pitches, tree skiing in superb backcountry and - most importantly - an abundance of deep dry powder. This first winter season, there are just four lifts (including The Revelation, almost two miles of gleaming new eight-person Swiss gondola, and a new high-speed quad chair called The Stoke) but they give access to four alpine bowls, and one run that is over eight miles long. Next year two more lifts will be added, and when work is complete there will be 21 lifts and 115 runs. The area currently covers 1,500 'skiable acres' and will eventually boast 10,000 more than any other North American resort. Even that, though, pales into insignificance when compared with the 500,000-acre area of the Selkirk Tangiers Helicopter skiing operation, which has been snapped up by the resort to make it easier for visitors to combine lift and helisking.

'Heliskiing, cat skiing, cross-country, back country, snowshoeing and downhill skiing can all be enjoyed almost on the same day if you've a mind to,' says the town's mayor, Mark McKee. 'It's caused a great sigh of relief to see the resort open at last, with all its opportunities and jobs, which will help stop youngsters leaving town to find work.'

This winter a day lift pass costs $56, a day's cat skiing costs $325, including lunch, while a taster day heliskiing, including three to four runs, costs $689. It's hardly cheap, but mixing one or two days' heliskiing with top-class lift skiing the rest of the week means a heliskiing holiday isn't necessarily just for the super-rich.

At the helm of the project is Paul Skelton, an amiable Australian workaholic affectionately known as 'Bones'. In almost 25 years in the business, Skelton has done just about everything possible in the ski industry. He started at Blackcomb (which was later absorbed by Whistler) as a snowcat driver grooming the slopes, moved on to the ski patrol, became the resort's avalanche forecaster and, after a spell as a heliskiing guide, became Whistler's mountain manager, where he collected valuable experience of capital development programmes including lift design, cutting new trails and snowmaking development. That someone so intimately connected with the undisputed big boy of North American skiing should have given it up to come to Revelstoke has to say something.

'We've got the hill, we've got the attitude and we've got the means,' he says. 'But we are not trying to compete with Whistler. We're going to be a very different sort of resort. For a start we have an established old town at our base - a real town with families going back generations - old logging families and railway families. We have fantastic terrain, with really long, thigh-burning runs and superb tree skiing. It's a real skiers' mountain.

'Our big challenge is how to grow without becoming too corporate - we aim to keep the common touch.'

In fact, developers have quietly discussed the potential of Revelstoke since the 1960s, but it wasn't until 2003 that plans solidified, with planning approval granted two years later. The new resort will be on three levels, and as well as the new lifts there will be a huge expansion of available accommodation. On the lower level of the new ski village, more than 200 condominiums are taking shape, alongside a major hotel. On the next level are the plots for family homes, of which more than $70m-worth were snapped up even before the resort opened. On a higher level still, more family plots are planned, only these will have a unique additional feature: helipads. 'This will enable families to be picked up by helicopter for a private day's skiing with their own guide and exclusive use of the helicopter,' says Skelton.

Although the developers are keen to play up that this is a $1bn project, it has to be said that the majority of this will go on the accommodation rather than the lifts. All in all there will be 2,000 new hotel rooms, 1,500 apartments, and 850 houses. The boom time is well and truly back.

'Five years ago, people were selling lots near the ski hill for $25,000 and couldn't get rid of them,' says Alan Mason, the city's economic development officer. 'Now they're selling them for $250,000 and people are lining up.'

If there is a snag, it's the five- or six-hour journey (depending on the weather) it takes to complete the 255 miles from Calgary, the closest airport to which you can fly direct from the UK. But even this obstacle could be removed in the coming years - already Powder Air runs charter flights in small aircraft direct from Calgary to Revelstoke's own airport, and the resort is attempting to encourage the establishment of a regular air shuttle on the route. Direct flights from Europe into Kelowna, 124 miles away, could eventually be possible, too.

But even if it does take a five-hour road trip, the rich pickings at journey's end will almost certainly be worth it.